endian_inl_utils.h (2851B)
1 // Copyright 2014 Google Inc. All Rights Reserved. 2 // 3 // Use of this source code is governed by a BSD-style license 4 // that can be found in the COPYING file in the root of the source 5 // tree. An additional intellectual property rights grant can be found 6 // in the file PATENTS. All contributing project authors may 7 // be found in the AUTHORS file in the root of the source tree. 8 // ----------------------------------------------------------------------------- 9 // 10 // Endian related functions. 11 12 #ifndef WEBP_UTILS_ENDIAN_INL_UTILS_H_ 13 #define WEBP_UTILS_ENDIAN_INL_UTILS_H_ 14 15 #ifdef HAVE_CONFIG_H 16 #include "src/webp/config.h" 17 #endif 18 19 #include "src/dsp/dsp.h" 20 #include "src/webp/types.h" 21 22 #if defined(WORDS_BIGENDIAN) 23 #define HToLE32 BSwap32 24 #define HToLE16 BSwap16 25 #else 26 #define HToLE32(x) (x) 27 #define HToLE16(x) (x) 28 #endif 29 30 #if !defined(HAVE_CONFIG_H) 31 #if LOCAL_GCC_PREREQ(4,8) || __has_builtin(__builtin_bswap16) 32 #define HAVE_BUILTIN_BSWAP16 33 #endif 34 #if LOCAL_GCC_PREREQ(4,3) || __has_builtin(__builtin_bswap32) 35 #define HAVE_BUILTIN_BSWAP32 36 #endif 37 #if LOCAL_GCC_PREREQ(4,3) || __has_builtin(__builtin_bswap64) 38 #define HAVE_BUILTIN_BSWAP64 39 #endif 40 #endif // !HAVE_CONFIG_H 41 42 static WEBP_INLINE uint16_t BSwap16(uint16_t x) { 43 #if defined(HAVE_BUILTIN_BSWAP16) 44 return __builtin_bswap16(x); 45 #elif defined(_MSC_VER) 46 return _byteswap_ushort(x); 47 #else 48 // gcc will recognize a 'rorw $8, ...' here: 49 return (x >> 8) | ((x & 0xff) << 8); 50 #endif // HAVE_BUILTIN_BSWAP16 51 } 52 53 static WEBP_INLINE uint32_t BSwap32(uint32_t x) { 54 #if defined(WEBP_USE_MIPS32_R2) 55 uint32_t ret; 56 __asm__ volatile ( 57 "wsbh %[ret], %[x] \n\t" 58 "rotr %[ret], %[ret], 16 \n\t" 59 : [ret]"=r"(ret) 60 : [x]"r"(x) 61 ); 62 return ret; 63 #elif defined(HAVE_BUILTIN_BSWAP32) 64 return __builtin_bswap32(x); 65 #elif defined(__i386__) || defined(__x86_64__) 66 uint32_t swapped_bytes; 67 __asm__ volatile("bswap %0" : "=r"(swapped_bytes) : "0"(x)); 68 return swapped_bytes; 69 #elif defined(_MSC_VER) 70 return (uint32_t)_byteswap_ulong(x); 71 #else 72 return (x >> 24) | ((x >> 8) & 0xff00) | ((x << 8) & 0xff0000) | (x << 24); 73 #endif // HAVE_BUILTIN_BSWAP32 74 } 75 76 static WEBP_INLINE uint64_t BSwap64(uint64_t x) { 77 #if defined(HAVE_BUILTIN_BSWAP64) 78 return __builtin_bswap64(x); 79 #elif defined(__x86_64__) 80 uint64_t swapped_bytes; 81 __asm__ volatile("bswapq %0" : "=r"(swapped_bytes) : "0"(x)); 82 return swapped_bytes; 83 #elif defined(_MSC_VER) 84 return (uint64_t)_byteswap_uint64(x); 85 #else // generic code for swapping 64-bit values (suggested by bdb@) 86 x = ((x & 0xffffffff00000000ull) >> 32) | ((x & 0x00000000ffffffffull) << 32); 87 x = ((x & 0xffff0000ffff0000ull) >> 16) | ((x & 0x0000ffff0000ffffull) << 16); 88 x = ((x & 0xff00ff00ff00ff00ull) >> 8) | ((x & 0x00ff00ff00ff00ffull) << 8); 89 return x; 90 #endif // HAVE_BUILTIN_BSWAP64 91 } 92 93 #endif // WEBP_UTILS_ENDIAN_INL_UTILS_H_